===================================================================
@@ -1250,132 +1250,27 @@ expand_builtin_prefetch (tree exp)
static rtx
get_memory_rtx (tree exp, tree len)
{
- tree orig_exp = exp;
rtx addr, mem;
- HOST_WIDE_INT off;
- /* When EXP is not resolved SAVE_EXPR, MEM_ATTRS can be still derived
- from its expression, for expr->a.b only <variable>.a.b is recorded. */
- if (TREE_CODE (exp) == SAVE_EXPR && !SAVE_EXPR_RESOLVED_P (exp))
- exp = TREE_OPERAND (exp, 0);
-
- addr = expand_expr (orig_exp, NULL_RTX, ptr_mode, EXPAND_NORMAL);
+ addr = expand_expr (exp, NULL_RTX, ptr_mode, EXPAND_NORMAL);
mem = gen_rtx_MEM (BLKmode, memory_address (BLKmode, addr));
- /* Get an expression we can use to find the attributes to assign to MEM.
- If it is an ADDR_EXPR, use the operand. Otherwise, dereference it if
- we can. First remove any nops. */
- while (CONVERT_EXPR_P (exp)
- && POINTER_TYPE_P (TREE_TYPE (TREE_OPERAND (exp, 0))))
- exp = TREE_OPERAND (exp, 0);
-
- off = 0;
- if (TREE_CODE (exp) == POINTER_PLUS_EXPR
- && TREE_CODE (TREE_OPERAND (exp, 0)) == ADDR_EXPR
- && host_integerp (TREE_OPERAND (exp, 1), 0)
- && (off = tree_low_cst (TREE_OPERAND (exp, 1), 0)) > 0)
- exp = TREE_OPERAND (TREE_OPERAND (exp, 0), 0);
- else if (TREE_CODE (exp) == ADDR_EXPR)
- exp = TREE_OPERAND (exp, 0);
- else if (POINTER_TYPE_P (TREE_TYPE (exp)))
- exp = build1 (INDIRECT_REF, TREE_TYPE (TREE_TYPE (exp)), exp);
- else
- exp = NULL;
+ /* Build a memory reference suitable for MEM_EXPR for use by the
+ alias oracle. Make sure to give that memory reference a proper
+ access size as well as alias-set zero. */
+ exp = fold_build2 (MEM_REF,
+ build_array_type (char_type_node,
+ build_range_type (sizetype,
+ size_one_node, len)),
+ exp, build_int_cst (ptr_type_node, 0));
/* Honor attributes derived from exp, except for the alias set
(as builtin stringops may alias with anything) and the size
(as stringops may access multiple array elements). */
- if (exp)
- {
- set_mem_attributes (mem, exp, 0);
-
- if (off)
- mem = adjust_automodify_address_nv (mem, BLKmode, NULL, off);
-
- /* Allow the string and memory builtins to overflow from one
- field into another, see http://gcc.gnu.org/PR23561.
- Thus avoid COMPONENT_REFs in MEM_EXPR unless we know the whole
- memory accessed by the string or memory builtin will fit
- within the field. */
- if (MEM_EXPR (mem) && TREE_CODE (MEM_EXPR (mem)) == COMPONENT_REF)
- {
- tree mem_expr = MEM_EXPR (mem);
- HOST_WIDE_INT offset = -1, length = -1;
- tree inner = exp;
-
- while (TREE_CODE (inner) == ARRAY_REF
- || CONVERT_EXPR_P (inner)
- || TREE_CODE (inner) == VIEW_CONVERT_EXPR
- || TREE_CODE (inner) == SAVE_EXPR)
- inner = TREE_OPERAND (inner, 0);
-
- gcc_assert (TREE_CODE (inner) == COMPONENT_REF);
-
- if (MEM_OFFSET_KNOWN_P (mem))
- offset = MEM_OFFSET (mem);
-
- if (offset >= 0 && len && host_integerp (len, 0))
- length = tree_low_cst (len, 0);
-
- while (TREE_CODE (inner) == COMPONENT_REF)
- {
- tree field = TREE_OPERAND (inner, 1);
- gcc_assert (TREE_CODE (mem_expr) == COMPONENT_REF);
- gcc_assert (field == TREE_OPERAND (mem_expr, 1));
-
- /* Bitfields are generally not byte-addressable. */
- gcc_assert (!DECL_BIT_FIELD (field)
- || ((tree_low_cst (DECL_FIELD_BIT_OFFSET (field), 1)
- % BITS_PER_UNIT) == 0
- && host_integerp (DECL_SIZE (field), 0)
- && (TREE_INT_CST_LOW (DECL_SIZE (field))
- % BITS_PER_UNIT) == 0));
-
- /* If we can prove that the memory starting at XEXP (mem, 0) and
- ending at XEXP (mem, 0) + LENGTH will fit into this field, we
- can keep the COMPONENT_REF in MEM_EXPR. But be careful with
- fields without DECL_SIZE_UNIT like flexible array members. */
- if (length >= 0
- && DECL_SIZE_UNIT (field)
- && host_integerp (DECL_SIZE_UNIT (field), 0))
- {
- HOST_WIDE_INT size
- = TREE_INT_CST_LOW (DECL_SIZE_UNIT (field));
- if (offset <= size
- && length <= size
- && offset + length <= size)
- break;
- }
-
- if (offset >= 0
- && host_integerp (DECL_FIELD_OFFSET (field), 0))
- offset += TREE_INT_CST_LOW (DECL_FIELD_OFFSET (field))
- + tree_low_cst (DECL_FIELD_BIT_OFFSET (field), 1)
- / BITS_PER_UNIT;
- else
- {
- offset = -1;
- length = -1;
- }
-
- mem_expr = TREE_OPERAND (mem_expr, 0);
- inner = TREE_OPERAND (inner, 0);
- }
-
- if (mem_expr == NULL)
- offset = -1;
- if (mem_expr != MEM_EXPR (mem))
- {
- set_mem_expr (mem, mem_expr);
- if (offset >= 0)
- set_mem_offset (mem, offset);
- else
- clear_mem_offset (mem);
- }
- }
- set_mem_alias_set (mem, 0);
- clear_mem_size (mem);
- }
+ set_mem_attributes (mem, exp, 0);
+ set_mem_alias_set (mem, 0);
+ /* ??? Not sure why we clear mem-size. */
+ clear_mem_size (mem);
return mem;
}